EEXI

EEXI stands for Energy Efficiency Existing Ship Index, an International Maritime Organization (IMO) regulation designed to reduce greenhouse gas emissions from existing ships by raising their energy efficiency. Adopted as part of amendments to MARPOL Annex VI, the EEXI provides a mechanism to verify that ships already in service meet a minimum energy efficiency level based on their current design and equipment.

Scope and basis: The rule applies to ships of 400 gross tonnage and above engaged in international voyages. For each vessel, an EEXI value is calculated using ship data such as hull and propulsion characteristics, engine power, service speed, and installed energy efficiency technologies. A ship-specific required EEXI value is determined by ship type and operating profile. Compliance means the vessel’s EEXI value does not exceed the required value.

Compliance options: When a vessel does not meet the required EEXI, operators may implement measures to improve efficiency (e.g., engine power limitation, hull and propeller optimizations, installation or upgrading of energy-saving devices, or speed reductions) or adopt other energy efficiency measures under the Ship Energy Efficiency Management Plan (SEEMP). Often, compliance is a combination of technical and operational measures.

Certification and surveys: An EEXI is verified by a flag state or a recognized organization and recorded on an EEXI certificate. The certificate is valid until the next required survey, at which time re-verification is performed, including any changes to the vessel that affect its energy efficiency.

Impact and context: EEXI is part of a broader IMO strategy to reduce CO2 emissions from international shipping and complements the Energy Efficiency Design Index (EEDI) for new ships and SEEMP requirements for ongoing operation.